Isolated computed tomography diagnosis of pulmonary contusion does not correlate with increased morbidity

Thoracic Imaging in Pediatric Trauma: Are CTs Necessary?

OBJECTIVES

Imaging algorithms for assessment of thoracic trauma in pediatric patients remain controversial, attempting to balance radiation dose and its associated risk with the need for thorough assessment of patients' injuries. This study reviewed the value of chest radiography in detecting traumatic injuries, and the impact that computed tomography (CT) had on clinical management.

METHODS

A retrospective review of pediatric trauma patients undergoing chest radiography and thoracic CT over a 2-year period at a level 1 trauma center was performed. The incidence of various traumatic injuries was documented, with measures of sensitivity and specificity on radiography. Clinical notes were reviewed to identify any changes in care based on CT findings.

RESULTS

Eighty-one pediatric trauma patients underwent thoracic CT over a 2-year period, with 60 patients meeting the inclusion criteria. Radiographs identified 47 traumatic injuries out of 117 seen on the subsequent CT examinations for a sensitivity of 41% and specificity of 91%. Radiographs were most sensitive in detecting osseous injuries with a sensitivity of 54%. Additional CT findings changed management in 2 of 60 cases, or 3.3% of the time.

CONCLUSIONS

Use of thoracic CT in pediatric trauma patients identifies a significantly greater number of injuries compared with than radiography but significantly increases radiation dose while changing management in only a very small proportion of cases. Despite the relatively small sample size, the findings reflect 2 years of experience at a level 1 trauma center, and this study suggests that it may be reasonable to decrease the frequency of cross-sectional imaging.

Chest x-ray vs. computed tomography of the chest in pediatric blunt trauma

INTRODUCTION

Chest x-ray (CXR) has been shown to be an effective detection tool for clinically significant trauma. We evaluated differences in findings between CXR and computed tomography of the chest (CCT), their impact on clinical management and the performance of the CXR.

METHODS

This retrospective study examined children (less than 18 years) who received a CXR and CCT between 2009 and 2015. We compared characteristics of children by conducting univariate analysis, reporting the proportion of additional diagnoses captured by CCT, and using it to evaluate the sensitivity and specificity of the CXR. Outcome variables were diagnoses made by CCT as well as the ensuing changes in the clinical management attributable to the diagnoses reported by the CCT and not observed by the CXR.

RESULTS

In 1235 children, CCT was associated with diagnosing higher proportions of contusion or atelectasis (60% vs 31%; p < .0001), pneumothorax (23% vs 9%; p < .0001), rib fracture (18% vs 7%; p < .0001), other fracture (20% vs 10%; p < .0001), diaphragm rupture (0.2% vs 0.1%; p = .002), and incidental findings (7% vs 2%; p < .0001) as compared to CXR. CCT findings changed the management of 107 children (8.7%) with 32 (2.6%) of the changes being surgical procedures. The overall sensitivity and specificity of the CXR were 57.9% (95% CI: 54.5-61.2) and 90.2% (95% CI: 86.8-93.1), respectively. The positive predictive value and negative predictive value were 93.1% and 48.6%, respectively.

CONCLUSION

CXR is a useful initial screening tool to evaluate pediatric trauma patients along with clinical presentation in the Emergency Department in children.

LEVEL OF EVIDENCE

Level III, diagnostic test.

Use of Chest Computed Tomography for Blunt Pediatric Chest Trauma: Does It Change Clinical Course?

INTRODUCTION

Given the concern for radiation-induced malignancy in children and the fact that risk of severe chest injury in children is low, the risk/benefit ratio must be considered in each child when ordering a computed tomography (CT) scan after blunt chest trauma.

METHODS

The study included pediatric blunt trauma patients (age, <15 years) with chest radiograph (CR) before chest CT on admission to our adult and pediatric level I trauma center. Surgeons were asked to view the blinded images and reads and indicate if they felt CT was warranted based on CR findings, if their clinical management change based on additional findings on chest CT, and how they might change management.

RESULTS

Of the 127 patients identified, 64.6% had no discrepancy between their initial CR and chest CT and 35.4% of the children's imaging contained a discrepancy. The majority of the pediatric and general trauma surgeons felt CT was indicated in 6 of 45 patients based on CR. In 87% of patients with a discrepancy in findings on CR and CT, the majority of surgeons agreed that their management would not change based on the additional information. In the 6 patients in which the CT was considered indicated, 4 of the 6 would have triggered a management change.

CONCLUSIONS

Our study suggests that chest CT scans frequently serve as confirmatory diagnostic tools and in the pediatric blunt chest trauma patient and can be withheld in many cases without hindering the management of an injured child.

Review of Interventions and Radiation Exposure from Chest Computed Tomography in Children with Blunt Trauma

OBJECTIVE

To determine the radiation risk to a child undergoing trauma evaluation with chest computed tomography (CCT) for every clinically actionable injury identified.

STUDY DESIGN

This observational, cross-sectional study included all blunt trauma patients under 18 years of age undergoing CCT in a single urban emergency department. Via a retrospective chart review, therapeutic interventions done exclusively for chest injuries identified on CCT scan were identified. Effective radiation from each CCT was calculated and averaged and the dose required to diagnose 1 management-changing chest injury was determined.

RESULTS

Of 209 children undergoing CCT over a 19-month period, 168 were victims of blunt trauma. Ten required an intervention specifically for a chest injury identified on CCT (suggesting development of 1 malignancy per 37 actionable injures identified). None required an intervention for an injury exclusively noted on CCT, as all 10 actionable injuries were apparent via other modalities (radiograph, ultrasound examination, clinical examination).

CONCLUSION

Although 10 uniquely actionable injuries were identified on CCT, none were found only on CCT. Because CCTs rarely modified management, the amount of radiation administered per management change was sufficiently high to recommend reconsideration of current imaging practice in this single-center study.

Pulmonary contusions in the elderly after blunt trauma: incidence and outcomes

BACKGROUND

In the general population with blunt chest trauma, pulmonary contusions (PCs) are commonly identified. However, there is limited research in the elderly. We sought to evaluate the incidence and outcomes of PCs in elderly blunt trauma admissions.

METHODS

We retrospectively reviewed the trauma registry at a level I trauma center for all blunt thoracic trauma patients aged ≥65 y, who were admitted between 2007 and 2015. The medical records of PC patients were reviewed.

RESULTS

There were 956 admissions with blunt thoracic trauma; of which 778 had no pulmonary contusion (NO) and 178 had PC. The major mechanisms of injury were falls (58.7% NO, 39.3% PC, P <0.001) and motor vehicle crash/motor cycle crash (35.6% NO, 51.7% PC, P <0.001). Rib fractures were present in 79.8% of PC and 73.8% of NO patients, P = 0.1. PC patients more often had serious (AIS ≥3) head/neck (30.3% versus 20.6%, P <0.001), abdomen (12.4% versus 6.6%, P <0.001), and extremity injuries (20.8% versus 11.4%, P <0.001). Complication (46.1% PC versus 26.6% NO, P <0.001) and mortality (14.0% PC versus 6.2% NO, P = 0.0003) rates were higher in PC patients. On multivariate logistic regression analyses, PC presence was significantly associated with mechanical ventilation (odds ratio 2.5), intensive care unit admission (odds ratio 2.3), and mortality (odds ratio 1.9).

CONCLUSIONS

Over 18.6% of elderly blunt thoracic trauma patients sustained PC, despite an often low energy mechanism of injury. The presence of a PC should prompt investigation for other serious intrathoracic and extrathoracic injuries. PC presence is associated with substantial morbidity and mortality.

Factors Predicting Lung Contusions in Critically Ill Trauma Children: A Multivariate Analysis of 330 Cases

PURPOSE

The aim of the study was to identify factors predicting lung contusion in trauma children.

METHODS

Retrospective study conducted for a period of 8 years (January 01, 2005-December 31, 2012) in a medical surgical intensive care unit. All trauma patients younger than 15 years were included. Two groups were compared: those with lung contusions (C+ group) and those without lung contusions (C- group).

RESULTS

We included 330 patients. The mean (SD) age was 7.6 (4.3) years. Chest injury was diagnosed in 70 patients (21.2%). All our patients needed mechanical ventilation. Lung contusions were diagnosed in 43 patients (13% of all patients and 61.4% of patients with chest trauma). In multivariate analysis, independent factors predicting lung contusion were road traffic accident (odds ratio [OR], 3.2; 95% confidence interval [CI], 1.2-8.6; P = 0.019), increased Pediatric Risk of Mortality (PRISM) score (OR, 1.1; 95% CI, 1.1-1.2; P = 0.017), hepatic contusion (OR, 4.8; 95% CI, 1.3-17.1; P = 0.017), and pelvic ring fracture (OR, 3.5; 95% CI, 1.1-10.5; P = 0.026). Death occurred in 46 patients (13.9%). Intensive care unit mortality was significantly higher in the C+ group (OR, 2.5; 95% CI, 1.2-5.4; P = 0.021). However, mortality was not different between the 2 groups after adjusting for PRISM score (OR, 1.2; 95% CI, 0.5-2.9; P = 0.752) or after adjusting for Injury Severity Score (OR, 0.7; 95% CI, 0.3-2.1; P = 0.565).

CONCLUSIONS

Lung contusion is common in critically ill children with chest trauma. The diagnosis should be considered in patients with road traffic accident, increased PRISM score, hepatic contusion, and pelvic ring fracture.

Assessment and Resuscitation in Trauma Management

The golden hour of trauma represents a crucial period in the management of acute injury. In an efficient trauma resuscitation, the primary survey is viewed as more than simple ABCs with multiple processes running in parallel. Resuscitation efforts should be goal oriented with defined endpoints for airway management, access, and hemodynamic parameters. In tandem with resuscitation, early identification of life-threatening injuries is critical for determining the disposition of patients when they leave the trauma bay. Salvage strategies for profoundly hypotensive or pulseless patients include retrograde balloon occlusion of the aorta and resuscitative thoracotomy, with differing populations benefiting from each.

Pulmonary Contusion and Traumatic Pneumatoceles in a Platform Diver with Hemoptysis

BACKGROUND

Injuries in divers resulting purely from impact with the water are uncommon in the published literature. We present a case report of pulmonary contusion in a young diver.

CASE REPORT

A young, healthy competitive platform diver landed flat on his back in the water from a dive of 10 meters. He complained of upper back pain and had an episode of hemoptysis after the dive. He was initially observed for 15 hours postinjury, and was discharged when three chest radiographs (CXRs) taken at 1, 7, and 11 hours postinjury did not show significant abnormalities. Thirty-six hours postinjury, the patient experienced repeat hemoptysis and returned to the emergency department, where a fourth CXR performed 43 hours postinjury was normal. A computed tomography (CT) scan revealed pulmonary contusion and traumatic subpleural pneumatoceles. The patient was admitted to the cardiothoracic ward for observation. He recovered well with conservative treatment and was discharged on the fifth day after injury with clearance for air travel. In this patient with a high-energy mechanism of rapid deceleration and hemoptysis at the scene, there may be grounds for performing a CT scan of the thorax at the time of the first presentation, although the CT findings did not change conservative management of this patient. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Emergency physicians should recognize that a dive into water may generate sufficient impact to produce a pulmonary contusion. If the patient is clinically well and the CXR results are normal, the decision to initiate a CT scan and subsequent disposition may be based on clinical judgement and institutional practice.

Pulmonary contusion in the pan-scan era

BACKGROUND

Although pulmonary contusion (PC) is traditionally considered a major injury requiring intensive monitoring, more frequent detection by chest CT in blunt trauma evaluation may diagnose clinically irrelevant PC.

OBJECTIVES

We sought to determine (1) the frequency of PC diagnosis by chest CT versus chest X-ray (CXR), (2) the frequency of PC-associated thoracic injuries, and (3) PC patient clinical outcomes (mortality, length of stay [LOS], and need for mechanical ventilation), considering patients with PC seen on chest CT only (SOCTO) and isolated PC (PC without other thoracic injury).

METHODS

Focusing primarily on patients who had both CXR and chest CT, we conducted a pre-planned analysis of two prospectively enrolled cohorts with the following inclusion criteria: age >14 years, blunt trauma within 24h of emergency department presentation, and receiving CXR or chest CT during trauma evaluation. We defined PC and other thoracic injuries according to CT reports and followed patients through their hospital course to determine clinical outcomes.

RESULTS

Of 21,382 enrolled subjects, 8661 (40.5%) had both CXR and chest CT and 1012 (11.7%) of these had PC, making it the second most common injury after rib fracture. PC was SOCTO in 739 (73.0%). Most (73.5%) PC patients had other thoracic injury. PC patients had higher admission rates (91.9% versus 61.7%; mean difference 30.2%; 95% confidence interval [CI] 28.1-32.1%) and mortality (4.7% versus 2.0%: mean difference 2.8%; 95% CI 1.6-4.3%) than non-PC patients, but mortality was restricted to patients with other injuries (injury severity scores>10). Patients with PC SOCTO had low rates of associated mechanical ventilation (4.6%) and patients with isolated PC SOCTO had low mortality (2.6%), comparable to that of patients without PC.

CONCLUSIONS

PC is commonly diagnosed under current blunt trauma imaging protocols and most PC are SOCTO with other thoracic injury. Given that they are associated with low mortality and uncommon need for mechanical ventilation, isolated PC and PC SOCTO may be of limited clinical significance.

Variation in Computed Tomography Imaging for Pediatric Injury-Related Emergency Visits

OBJECTIVE

To assess variation in the use of computed tomography (CT) for pediatric injury-related emergency department (ED) visits.

STUDY DESIGN

This was a retrospective cohort study of visits to 14 network-affiliated EDs from November 2010 through February 2013. Visits were identified by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes. Primary outcome was CT use. We used descriptive statistics and performed multivariable logistic regression to evaluate the association of patient and ED covariates on any and body region-specific CT use.

RESULTS

Of the 80 868 injury-related visits, 11.4% included CT, and 28.4% of those involved more than 1 CT. Across EDs, CT use ranged from 7.6% to 25.5% of visits and did not correlate with institutional Injury Severity Score (P = .33) or admission/transfer rates (P = .07). In multivariable analysis of nonpediatric EDs, trauma centers and nonacademic EDs were associated with CT use. Higher pediatric volume was associated with any CT use; however, there was an inverse relationship between volume and nonhead CT use. When the pediatric ED was included in multivariable modeling, the effect of level 1-3 trauma center designation remained, and the pediatric level 1 trauma center was less likely to use most body region-specific CTs.

CONCLUSION

There is wide variation in CT imaging for pediatric injury-related visits not attributable solely to case mix. Future work to optimize CT utilization should focus on additional factors contributing to imaging practices and interventions.

Pediatric Blunt Thoracic Trauma

Thoracic injury in children deserves special attention because, although it accounts for less than 10% of traumatic injuries in children, there is a significant associated morbidity and mortality. This review discusses the anatomic and physiologic factors resulting in such injury severity with blunt thoracic trauma in children. Specific organ injuries, including most common chest wall injuries, hemo- and pneumothoraces, and pulmonary parenchymal injuries, are discussed, encompassing epidemiology, presentation, diagnosis, and management. Rare injuries including tracheobronchial tree injuries, cardiovascular injuries, esophageal injuries, and diaphragmatic injuries are also briefly discussed.

The SCRAP rule: The Derivation and Internal Validation of a Clinical Decision Rule for Computed Tomography of the Chest in Blunt Thoracic Trauma

Objective:

To derive and internally validate a clinical decision rule that will rule out major thoracic injury in adult blunt trauma patients, reducing the unnecessary use of chest computed tomographic (CT) scans.

Methods:

Data were retrospectively obtained from a chart review of all trauma patients presenting to a Canadian tertiary trauma care centre from 2005 to 2008, with those from April 2006 to March 2007 being used for the validation phase. Patients were included if they had an Injury Severity Score &gt; 12 and chest CT at admission or a documented major thoracic injury noted in the trauma database. Patients with penetrating injury, a Glasgow Coma Scale (GCS) score ≤ 8, paralysis, or age &lt; 16 years were excluded.

Results:

There were 434 patients in the derivation group and 180 in the validation group who met the inclusion criteria. Using recursive partitioning, five clinical variables were found to be particularly predictive of injury. When these variables were normal, no patients had a major thoracic injury (sensitivity 100% [95% CI 98.4–100], specificity 46.9% [95% CI 44.2–46.9], and negative likelihood ratio 0.00 [95% CI 0.00–0.04]). The five variables were oxygensaturation (&lt; 95% on room air or &lt; 98% on any supplemental oxygen),chest radiograph, respiratoryrate ≥ 25, chestauscultation, and thoracicpalpation (SCRAP). In the validation group, the same five variables had a sensitivity of 100% (95% CI 96.2–100%), a specificity of 44.7% (95% CI 39.5–44.7%), and negative likelihood ratio of 0.00 (95% CI 0.00–0.10).

Conclusions:

In major blunt trauma with a GCS score &gt; 8, the SCRAP variables have a 100% sensitivity for major thoracic injury in this retrospective study. These findings need to be prospectively validated prior to use in a clinical setting.

Computed tomographic assessment of lung weights in trauma patients with early posttraumatic lung dysfunction

Introduction

Quantitative computed tomography (qCT)-based assessment of total lung weight (M_lung) has the potential to differentiate atelectasis from consolidation and could thus provide valuable information for managing trauma patients fulfilling commonly used criteria for acute lung injury (ALI). We hypothesized that qCT would identify atelectasis as a frequent mimic of early posttraumatic ALI.

Methods

In this prospective observational study, M_lung was calculated by qCT in 78 mechanically ventilated trauma patients fulfilling the ALI criteria at admission. A reference interval for M_lung was derived from 74 trauma patients with morphologically and functionally normal lungs (reference). Results are given as medians with interquartile ranges.

Results

The ratio of arterial partial pressure of oxygen to the fraction of inspired oxygen was 560 (506 to 616) mmHg in reference patients and 169 (95 to 240) mmHg in ALI patients. The median reference M_lung value was 885 (771 to 973) g, and the reference interval for M_lung was 584 to 1164 g, which matched that of previous reports. Despite the significantly greater median M_lung value (1088 (862 to 1,342) g) in the ALI group, 46 (59%) ALI patients had M_lung values within the reference interval and thus most likely had atelectasis. In only 17 patients (22%), M_lung was increased to the range previously reported for ALI patients and compatible with lung consolidation. Statistically significant differences between atelectasis and consolidation patients were found for age, Lung Injury Score, Glasgow Coma Scale score, total lung volume, mass of the nonaerated lung compartment, ventilator-free days and intensive care unit-free days.

Conclusions

Atelectasis is a frequent cause of early posttraumatic lung dysfunction. Differentiation between atelectasis and consolidation from other causes of lung damage by using qCT may help to identify patients who could benefit from management strategies such as damage control surgery and lung-protective mechanical ventilation that focus on the prevention of pulmonary complications.

Lung contusion in children--early computed tomography versus radiography

OBJECTIVE

To investigate, in children, the correlation between the extent of lung contusion as detected on early radiologic examination (chest radiograph [CXR] and/or thoracic computed tomography [TCT]) and subsequent clinical outcome measures.

DESIGN

Retrospective chart review study with blinded assessment of thoracic imaging.

SETTING

A university-affiliated, level 1 designated pediatric trauma center.

INTERVENTIONS

None.

PATIENTS

Patients (1-18 yrs) who, between April 2000 and October 2005, were diagnosed with lung contusion were eligible for study entry. The medical records of those patients who underwent early (within the first 24 hrs of admission) thoracic imaging (CXR and/or TCT) were reviewed. A pulmonary contusion score (PCS) was assigned to each thoracic image according to the extent of contusion injury by two investigators blinded to each others score and the clinical details of the patient.

RESULTS

Seventy-four patients were included in the study. Twenty patients had undergone CXR only, whereas 54 had undergone both CXR and TCT. The mean PCS on CXR was 3.9 +/- 3.6 compared with 6.5 +/- 3.49 on TCT (p < .001). In eight patients (15%) who underwent TCT and CXR, the CXR failed to demonstrate a lung contusion. The PCS derived from CXR examination correlated positively with lower Pao2/Fio2 (r = -.36, p = .019), higher ventilation index (r = .35, p = .014), and longer length of ventilation (r = .28, p = .019). No such correlation was seen with TCT-derived PCS.

CONCLUSIONS

The severity of lung contusion determined by CXR, but not TCT, correlates with impairment of oxygenation, CO2 exchange, and duration of ventilatory support.

The imaging of paediatric thoracic trauma

Major chest trauma in a child is associated with significant morbidity and mortality. It is most frequently encountered within the context of multisystem injury following high-energy trauma such as a motor vehicle accident. The anatomic-physiologic make-up of children is such that the pattern of ensuing injuries differs from that in their adult counterparts. Pulmonary contusion, pneumothorax, haemothorax and rib fractures are most commonly encountered. Although clinically more serious and potentially life threatening, tracheobronchial tear, aortic rupture and cardiac injuries are seldom observed. The most appropriate imaging algorithm is one tailored to the individual child and is guided by the nature of the traumatic event as well as clinical parameters. Chest radiography remains the first and most important imaging tool in paediatric chest trauma and should be supplemented with US and CT as indicated. Multidetector CT allows for the accurate diagnosis of most traumatic injuries, but should be only used in selected cases as its routine use in all paediatric patients would result in an unacceptably high radiation exposure to a large number of patients without proven clinical benefit. When CT is used, appropriate modifications should be incorporated so as to minimize the radiation dose to the patient whilst preserving diagnostic integrity.

The lung and pediatric trauma

Thoracic trauma is relatively frequent in children and causes considerable mortality. This is mainly due to the multiorganic nature of the trauma. The lung is more often affected even in the absence of rib fractures because of the considerable pliability of the chest wall that allows direct transfer of energy to this organ. Injuries to the heart, the aorta, the esophagus, and the diaphragm are rare. Lung contusion and laceration cause parenchymal hemorrhage and consolidation sometimes accompanied by pneumothorax and/or hemothorax. Tracheobronchial disruption is rare but life-threatening. Most traumatic lung injuries may be treated with rest, respiratory support, and eventually intercostal drainage. Large hemorrhage may require thoracotomy, and persistent pneumothorax (indicative of tracheobronchial disruption) may require intubation with fiberoptic bronchoscopic assistance and eventually reparative or ablative surgery. Adult respiratory distress syndrome is very rarely seen in children with thoracic trauma, but it remains highly lethal.

Using 99mTc-DTPA radioaerosol inhalation lung scan as compared with computed tomography to detect lung injury in blunt chest trauma

BACKGROUND

Detection of pulmonary contusion in patients with blunt chest trauma is very important so as to commence therapy immediately to avoid irreversible damage. The purpose of our study was to evaluate the efficacy of technetium-99m diethylene triamine pentaacetic acid (99mTc-DTPA) aerosol inhalation lung scintigraphy in comparison with chest computed tomography (CT) in the diagnosis of pulmonary contusion at acute blunt chest trauma.

METHODS

Twenty-nine patients with isolated blunt chest trauma were referred to the emergency department of our hospital, and nine healthy people participated in this study. Sixteen patients who had pulmonary contusion on CT scans were referred to as group 1, and 13 patients who had normal CT scans as group 2. Nine healthy people comprised a control group. 99mTc-DTPA aerosol inhalation lung scintigraphy was performed on the first day in all patients.

RESULTS

The mean half time (T1/2) and penetration index values of 99mTc-DTPA clearance were significantly lower in groups 1 and 2 compared with the control group. Among the three groups, there were no significant differences in arterial blood gas analysis except for PO2. The mean T1/2 value of 99mTc-DTPA clearance did correlate with PO2 values but not with pH, PCO2, or HCO3 values.

CONCLUSIONS

99mTc-DTPA radioaerosol inhalation lung imaging may serve as a useful adjunct and supportive method to chest CT scanning for detecting mild pulmonary contusion.